Glass alkali metal gas chamber internal alkali metal vapor atom density measuring device and method

The invention discloses a glass alkali metal gas chamber internal alkali metal vapor atom density measuring device and method. A Faraday modulator is arranged between a polarizer and a measurement sensitive unit module; linearly polarized light from the polarizer can generate a Faraday rotation angle of a polarization plane of the linearly polarized light in the Faraday modulator due to a Faradayeffect; a Faraday deflection angle of a polarization plane is generated through the measurement sensitive unit module, and the Faraday deflection angle is demodulated through the combination of a photoelectric detector and a lock-in amplifier; the atomic density of the alkali metal vapor in the measurement sensitive unit module is calculated by utilizing a relational expression between a Faraday deflection angle and the atomic density of the alkali metal vapor, and the method can be used for evaluating the atomic density of the alkali metal vapor in an atom sensing device. In particular, the present invention has high